1. Field of the Invention
The present invention relates to an electrolysis apparatus for effecting electrolysis of an organic electrolytic solution comprising an organic solvent and an electrolyte dissolved therein to obtain an organic compound.
2. Description of the Background Art
In a conventional electrolysis apparatus, in order to obtain an organic compound by electrolysis of an organic electrolytic solution comprising an organic solvent and an electrolyte dissolved therein, an anode and a cathode are inserted in the organic electrolytic solution contained in an electrolytic cell, and electric power is suppled to the two electrodes. In another conventional electrolysis apparatus, as shown in FIG. 1, a diaphragm 2 such as an ion exchange membrane is provided in an electrolytic cell 1 to separate the cell 1 into cathode and anode compartments 3 and 5, and an organic electrolytic solution 4 comprising an organic solvent and an electrolyte dissolved therein, and an electrolytic aqueous solution 6 are contained in the cathode and anode compartments 3 and 5, respectively. Electric power (not shown) is supplied to a cathode 7 and an anode 8 inserted in the organic electrolytic solution 4 and the electrolytic aqueous solution 6 of the cathode and anode compartments 3 and 5 to perform the electrolysis of the organic electrolytic solution to obtain an organic compound, for example, adiponitrile or the like.
In such conventional electrolysis apparatuses, since a lead plate is usually used for the anode, the organic compound adsorbs over the surface of the anode without question in the cell with no diaphragm, and the organic compound passing through the diaphragm also adsorbs over the surface of the anode even in the cell having the diaphragm. Thus, the surface area where the current flows is decreased to reduce the electric current density, resulting in that the production efficiency or productivity of the organic compound is largely reduced.
In this case, considering the productivity, the voltage is to be increased to invite the acceleration of the electrode elution. Further, on the surface of the lead (Pb) anode, a .beta.-PbO.sub.2 film grows to thicken during the operation and a peeling of the .beta.-PbO.sub.2 film off the anode is caused. Accordingly, the anode becomes more slender, and the distance between the electrodes is enlarged to further cause the reduction of the electric current density.
Relating to the cathode, even when the cathode is prepared by a porous material in order to increase the reaction speed, the pores of the cathode are occupied by the gas such as hydrogen generated from the cathode, and hence, the reaction speed is not so increased and becomes equal to that of the flat plate cathode. Furthermore, the reaction gas such as carbon monoxide (CO) or the like is hard to dissolve in the electrolytic solution, and pressurization is sometimes required.